自邻甲酚制备的水杨醛合成香豆素的研究

Study on Synthesis of Coumarin by Using Salicylaldehyde Prepared from o-Methyl Phenol

以自邻甲酚制备的97%水杨醛为原料,研究合成香豆素的最佳条件。反应中添加醋酸苯酯作为溶剂,醋酸苯酯可以循环使用;醋酐与水杨醛的用量比为2.17 1(物质的量比),相比以往采用苯酚方法制备的水杨醛为原料,醋酐用量减少30%;反应最佳温度为190℃,反应最佳时间为6 h。

The synthesis of coumarin by using 97% salicylaldehyde that prepared from o-methyl phenol as starting material was investigated and the optimum synthesis conditions were obtained as follows: phenyl acetate was used as solvent that could be recycled and reused in this process,the molar ratio of acetic anhydride to salicylaldehyde was 2.17/1,there was a decrease of 30% in the dosage of acetic anhydride compared with that of using salicylaldehyde prepared from phenol as starting material,and reaction temperature was 190 ℃,reaction time was 6 h.